Daikin VRV

Daikin VRV Error Code U6

Troubleshooting guide for the Daikin VRV system fault U6.

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What It Means

Malfunction of transmission between indoor units.

Possible Causes

  • Faulty wiring.
  • External factor (Noise etc.).
  • Defective indoor unit PCB.

Not sure which one it is — or if it's none of these? Try ACLogics today.

Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
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Full Diagnosis

Malfunction of transmission between indoor units

All Recorded Causes

Faulty wiring External factor (Noise etc.) Defective indoor unit PCB

Verify Before Replacing Parts

  1. Confirm the exact Daikin model family and vrv context before acting on a generic code description.
  2. Start with line voltage, low voltage, and board output checks in sequence so the fault is isolated cleanly — the data plate flags faulty wiring.
  3. Inspect connectors, relay outputs, and any recently replaced electrical parts for mismatch or loose fit, and verify external factor (Noise etc.).
  4. After the correction, run the system long enough to confirm the vrv fault does not return under normal load.

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